I don't know about that. the resources of the ark are supposed to be dwindling so there probably isn't a lot of airplane fuel and if you don't know where you're going or how far land is I don't think the best form of transportation is by plane.
+1
They will probably be traveling by boat, and if they did travel by air, how many people could the plane hold? There is alot of people who want to leave and i don't think that one plane can carry them all, sure they can send a few people in the plane to look for the land, but there isn't alot of resources so i don't think they can manage going back to the ark to pick up people/tell them, and actually finding land/getting to it would take up alot of fuel most likely.